#include "ScreenPtr.h"
Screen& ScreenPtr::operator++(){
	//...
	return *++ptr;
}
Screen& ScreenPtr::operator--(){
	//...
	return *--ptr;
}
Screen& ScreenPtr::operator++(int){
	//...
	return *ptr++
}
Screen& ScreenPtr::operator--(int){
	//...
	return *ptr--;
}